In Drill Down Graph PRO, you can customize not just nodes, but also individual links. This way, you can use links as a data storytelling tool, making the meaning and significance of each relationship readily apparent to the report user.

Head to the Format Visual tab and explore the various settings within the Links (default category) sections to adjust the default settings for all links, including link style, color mode, thickness, decorations, and more. 

Furthermore, if you have created custom link categories with the Link Category Class field, each category will have its own Link Category X section that you can use to apply settings to all links within that category.

If you want to apply individual settings to a specific link, you can use the custom fields to override the default settings, including link color, thickness, display label, and more. You can even feature custom text or URL in the tooltip. Read more about custom fields in the Setting Up Fields page.